Portable X-ray unit



March 26, 1957 c. E. BOUCHER PORTABLE x-RAY UNIT 2 Sheets-Sheet 1 Filed Dec. 14, 1953 INVENTOR.

CORMA`CK E. BOUCHER ATTORNEY March 26, 1957 Filed Dec.

c. E. BOUCHER 2,786,948

PORTABLE X-RAY UNIT 2 Sheets-Sheet 2 nited States Patent O PORTABLE X-RAY UNIT Cormack E. Boucher, Seattle, Wash. Application December 14, 1953, Serial No. 398,103

7 claims. (Cl. 25o- 87) The present invention relates to X-ray apparatus and more particularly to a lightweight, mobile X-ray apparatus adapted particularly for radiographic field inspection of industrial equipment.

It is an object of :the invention to provide a compact, relatively lightweight X-ray apparatus that may easily be carried about manually.

A further object of the invention isto provide new and improved means for supporting an X-ray tube within portable, lightweight X-ray apparatus.

Another object of the invention is to provide an X-ray apparatus capable of generating two useful X-ray beams of different intensi-ties.

A further object of the invention is to provide lightweight, compact X-ray apparatus that may be easily assembled or disassembled.

Other objects and advantages of the invention will become more apparent hereinafter.

In accordance with the illustrated embodiment of the present invention, an X-ray apparatus is provided comprising a housing in which is mounted a power supply transformer having a pair of spaced apart windings. A double portal X-ray tube is mounted on the windings, the tube being lso positioned in the housing that two X-ray beams of different intensities emerge from spaced areas of the housing.

For a more complete description of the invention, reference is made to the accompanying drawings and the following description thereof.

In the drawings,

Fig. 1 is a longitudinal side elevation of the apparatus of the invention, the housing of the apparatus being shown in longitudinal medial section substantially along line 1 1 of Fig. 2;

Fig. 2 is a top plan view of the apparatus of the invention with the housing shown in section substantially along line 2 2 of Fig. l;

Fig. 3 is an end view of the apparatus of the invention with one of the end domes of the housing removed, the View being substantially in the direction of the arrows 3 3 of Fig. l;

Fig. 4 is a sectional view taken along line 4 4 of Fig. 1, and illustrating details of the X-ray tube support;

Fig. 5 is an enlarged sectional View taken along line 5 5 of Fig. 2 showing certain details of the X-ray tube of the apparatus;

Fig. 6 is a sectional View taken substantially along line 6 6 of Fig. 5;

Fig. 7 is a sectional view taken substantially along line 7 7 of Fig. 5;

Fig. 8 is a fragmentary view taken along line 8 8 of Fig. 2 and showing certain details of the apparatus; and

Fig. 9 is a schematic View of the electrical circuit of the apparatus.

Referring now to the drawings, the X-ray apparatus of the invention comprises a tubular housing 10 including a generally cylindrical portion 11 and removable end domes 12, 13 on each of the opposite ends thereof. The

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portion 11 and the end domes 12, 13 are provided with cooperating flanges 14, 15, respectively, by means of which the end plates may be secured in position. Preferably a gasket 16 is positioned between the flanges to enable the housing to be hermetically sealed and to prevent escape of the fluid dielectric medium with which the housing 10 is filled as will be explained hereinafter.

The housing 10 is preferably formed of magnesium or other suitable lightweight material so that the apparatus will be as light in weight as possible. Mounted within the housing 10 a transformer having a rectangular coretype core 17. As may be seen most clearly in Fig. 2, the core is elongated with the longer legs 18 of the core extending parallel to the axis of the housing 10. The transformer is supported by means of the opposite pairs of upper and lower shelves 19, 20, respectively, provided on opposite walls of the housing 10 and between which shelves the longer core legs 18 are slidably received. The shelves 19, 20 are welded to the walls of the housing and each shelf is braced by means of a pair of brackets 22 spaced near the opposite ends of the shelf. Extending between each pair of upper and lower shelves 19, 20 at each of the opposite ends thereof is a bolt 24 by means of which the shelves may be drawn together tightly to clamp the core legs 18 therebetween. To space the transformer properly within the housing 10, spacer blocks 26 are provided at each of the corners of the transformer core to space the core in relief `from the wall of the housing and accurately between the bolts 24.

Provided on the short, opposite end legs 27 of the transformer core which extend transversely of the housing, are windings or coils 28, 29. Power supply connection tothe primary of the transformer windings is effected through leads 32 connected 'to terminals 33 extending through the side wall of the housing and a terminal pad 37, and suitably insulated therefrom. A suitable power supply and control circuit is the subject of my copending application Serial No. 398,032, tiled December 14, 1953 (Docket2863).V VThe Iterminal 34-is for a ground connecton to the secondary of the winding 29 to which it is connected by a lead 36 and for a further purpose to be' more clearly explained hereinafter, the ground connection being shown at 35 in this instance. The secondary of the winding 29 is grounded to the transformer core 17 as indicated at 38.

The diameters of the windings 28, 29 are substantially equal but are substantially less than the length of the aperture of the core 17 whereby, as will be noted from the drawings, the windings are spaced a substantial distance from one another to provide an aperture extending transversely of the transformer. Mounted between the windings 28, 29, is an X-ray tube 40 comprising a glass envelope 41 (Fig. 5) having an overall length slightly less than the lengthof the core aperture. Means are provided on the windings for supporting the tube 40 on one side of the core with the axis of the tube extending substantially parallel to the longitudinal axis of the core and with the envelope 41 spaced at least partially inwardly of a plane tangential to the periphery of the windings 28, 29. Secured to each of the windings 28, 29 is a pair of split rings 45, 46, respectively, which are adapted to be clamped toythe windings in each instance by a screw 44. The screw 44 should in each instance be insulated from at least one end of respective rings to prevent the establishment of high circulating currents through the rings. Secured one to each pair of rings 45, 46 by resilient arms 47 is a pair of vertically extending tube supports 48, 49 consisting of a flat sheet of silicone glass fabric laminate. As most clearly illustrated in Fig. 4 each support has an aperture in the upper end thereof in which is received the corresponding end of the tube 40. The supports 48, 49 are split through to the aperture andare adapted to be clamped emerge from the envelope of the tube.

tothe tube by means of a clip 50 engaging ears V The supports 48, 49 have a certain degree of ilexiblllty 1n a direction at right angles to their general plane and togetherfwith the resiliency provided by. Vthe arms471e11d resilientl support` tothetube 40 wherebyit' will not be readily `injuredbb'y4 jars or shocks imparted to thehousin10. gWith reference to'FigS, l and3, it will be noted-thatin the apparatus as shown the transformer is mounted -with its horizontal medialV pllanepositioned below the ax1s of thel housing 10.V This is necessary to provide sufficient space above the transformer forrmountingof theX-ray tube 40. AOn the other hand, mounting ofthe X-ray tube withat least a portion .ofj itV spaced below the top of the transformer coils 28, 29 permits Vuse of a housing of minimum diameter, all of which contributes to the relatively light weight of theV apparatus. Y

Referring now more particularly to Fig. 5, theX-ray tube 40v includes `Xray generating means comprising a cathode means 60 and a double portal shieldedor hooded anodeV 62. Such tubes are available commercially and all of the details of such a tube need not be set forth here.

The anode hood 66 is formed of relatively thick `copper or other suitable material and is provided` with a pair of diametric apertures or portals 67, 68 therein lthrough which the generated X-rays may pass, whereby a pairofV relativelyropposite,conelike X-ray beams 71, 72 Y In certain double portal tubes, Vthe axes of the X-raykbeams are not exactly diametric, but are slightly inclined with respect to one another as indicated bythe dotted lines 69, 70 (Fig. 5) which represent the axes of the beams 71, 72, respectively. Referring now more particularly to Figs. l and 2, the X-ray tube is mounted between the windings 28, 29 whereby one of the beams, for example, the beam 72 is projected through the V'transverse aperture of the Vtransformer' while the path of the other beam 71 is projected upwardly and through theV wall of the housing directly adjacent thereto. Inasmuch as magnesium is relatively transparent to X- rays, no interference to the passage thereof through the wall-s of theV housing will result. With particular reference to Figs. 1 and 3, it will be noted that the X-ray tube is mounted* in offset relation with Arespect to the axis of the housing and that the axis 70 of the beant72 substantiallyrintersects the axis of the housing. At their respective points of emergence from the envelope of-v the X-ray tube 40, each of the. beams 71, 72 lis of substantially the same intensity and cross-sectional area. However, at their respectiveV areas of emergence from the housing 10, the beams 71,72 will differ substantially in their intensity because of the diiference in `distance from the anode. The beam 71 will be relatively concentrated and of great intensity while the beam 72'wil1 be dispersed over a'greatr area and hence relatively low in intensity. In using the. apparatus it is ordinarily positioned immediately adjacentV the work beingX-rayed with an X-ray sensitive nlm disposed upon the opposite side of the work. For identifying the window areas of the housingga port ring 81 -is secured to the housing about'the 'path of the beam 71 and a somewhat larger ring 82 islsecured on the opposite sideof the housingaboutthe path of the bean1-72. fDuringY operation of the Xlray tube both beams 71, -72 will be generated, thoughV ordinarily only oneof thebeams will be utilized in any given X-ray operation. If the material being X-rayed isv relatively thick, then the X-ray beam 71 willbe used. On `the other hand, if the material During operation of the tube, considerable heat will be generated at the anode. To assist in radiating the heat, there is provided a heat radiator 86 secured to the stem 87 of the anode 62. As shown most clearly in Fig. 5, the anode stem 87 comprises an elongated extension which is received in a cooperative opening formed in the body of the radiator 86. The radiator is provided with slots 88 on the top and sides thereof to increase the eifective area thereof for radiating the anode heat to the liling gas in the housing 10. The radiator may be secured to the anode by a set screw 89. The high voltage terminal of the winding 28 consists of a button 90 and is engaged by a contact spring 91 secured to the un'der side of the radiator 86 to provide the high voltage connection to the anode 62. The spring 91 also acts as a snubber to reduce vibrational shock to the tube. Provided on the secondary winding of the coil 29 is a filament voltage winding 92 connected by leads 93 to the filament of the tube.. Upon removal of the ground connection 35 from the terminal 34, the latter may be used to measure the current ow through the tube 40. The electricalcircuit of the apparatus is schematically illustrated in Fig. 9. Y

,Since vthe tube operates at a relatively high potential and is in close proximity to the housing 10, semicircular insulating plastic shields 94, 95 preferably lare 'mounted at each of the opposite ends of the vtube to prevent-arc over between the terminal ends ofthe tube and housing. Y The shields 94, 95 are supported on the ring assemblies 45, 46, respectively, by suitable brackets of insulating material indicated at 96.

While the housing 10 may `be lled with zin-insulating liquid, in order to keep the weight of the apparatus at a minimum, the housing is preferably filled with a gaseous insulating medium under pressure. Numerous insulating gases are available commercially. Gas may be introduced to thehousing through the valve fitting 97 mounted in the side Wall of the housing and the pressure may be observed by means of a pressure indicator 98, both of which extend through the terminal pad 37. The valve fitting 97, gauge 92E-and terminals 33 and 34 are protected by cover 99.

X-ray apparatus made in accordance with the invention is relatively compact and light in weight and hence may be easily carried about and maneuvered to place in proper position for X-ray examination of a desired object or struct-ure.v The assembly of the apparatus in the rst instance is relatively easily accomplished since the X-ray tube and transformer may be assembled as a unit exteriorly of the housing and thereafter the transformer may be simply` slid into place between the shelves 19, 20 and the securing bolts 24 tightened after the spacer blocks 26 are positioned. If, for some reason, it is desired to dismantle the'apparatus, for example, for repair or replacebeing X-rayed is relatively thin or for some other reason a A low intensity beam is d esifred,'thenY the X-ray beam 72 may be'used. To shield the unused X-'ray and to reduce Ythe health hazard, a shield is preferably provided-to close off the unused beam. a As shown, alead cap 83 may be provided and vsecured in a suitable manner tothe port 81 to shield off the'beamr71when the same is not to beused. In similar manner, a lead cap (not shown) may be secured to the ring `82 when the beam 72 isnot to be used. r

ment of some part, the end domes 12, 13 are rst removed, bolts 24 and spacer blocks 26 then removed from the'shelves V19, 20 and thetransformer and X-ray. tube then :slid out of the housing whereby the various parts willfbe easily accessible for repair of the same.

Having illustrated and described a preferred embodiment ot' the invention, it should be apparent `to those skilled in the art that the invention permits of modification inV arrangement and detail. I claim as my invention all such modifications as come within the true spirit and scope ofthe appended claims.

Il. AnVX-ray apparatus comprising a sealed housing, a high tension transformer in said housing, said transformer comprising a rectangular core-typecore,,windings lon a pairl of opposite legsof said core, saidA windings being spaced apart to provide an Vaperture transversely of said transformer," an lX-ray tube for'generating anX-ray beam, and means on said windings for supporting said X-ray tube Withsaid vX-ray beamprojecting through said aperture. Y, "2. X-ray apparatus comprising means yforming a'tubnlarhousing. of material hav'ing'e'a lowX-rayabsorplioncelicient, an X-ray tube and transformer therefor mounted within said housing, said transformer comprising a rectangular core-type core and windings on one pair of opposite legs of said core, means mounting said X-ray tube on said windings, and means lixedly to secure said transformer and tube in said housing including shelf means on the inner wall of said housing and extending longitudinally thereof for slidably receiving the winding free legs of said transformer core and supporting the same.

3. An X-ray apparatus comprising an elongate tubular housing, an X-ray tube and power supply transformer therefor mounted within said housing, said transformer comprising a rectangular core-type core having a width slightly less than the linternal diameter of the housing, said core being xedly secured in said housing in spaced relation to the walls thereof with the longer legs of the core extending longitudinally of the housing, each of the shorter legs of said core having a circular winding thereon of substantially equal diameter, said diameter being substantially less than the length -of the aperture of said core whereby said windings are spaced a substantial distance from one another, said X-ray tube comprising an elongate envelope having a length less than said aperture length, and means on said windings supporting said tube on one side of said core with the axis thereof extending parallel to the longitudinal axis of said core and with the entire length of said envelope spaced at least partially inwardly of a plane tangential to the periphery of said windings.

4. An X-ray apparatus comprising a tubular housing of X-ray transparent material, an X-ray tube in said housing including an elongate envelope and X-ray generating means in said envelope for generating a pair of laterally emerging X-ray beams directed substantially diametrically, said tube being mounted closely adjacent one side of said housing with the axis of the path of one of said beams intersecting the axis of said housing, a high tension transformer for said tube comprising a rectangular coretype core xedly mounted in said housing with one pair of legs of the core spaced substantially equidistantly on the opposite sides of the plane defined by the axis of said housing and the axis of said one beam, and with the other pair of legs of `said core spaced substantially equidistantly on the opposite sides of a plane normal to said housing axis and parallel to and intersecting said beam axis, a coil winding on each of said other pair of legs, said windings being spaced apart to provide a passageway iior said one beam, and means on said windings for engaging the opposite ends of said envelope to support the same,

5. X-ray apparatus comprising a transformer including a rectangular core-type core having windings ou a pair of opposite legs of said core, an X-ray tube comprising an elongate envelope and means mounting said tube on said windings including a pair of elongate, parallel, spaced apart sheets of electrical insulating material each having an aperture adjacent one end for receiving an end of said tube envelope, means clamping said sheets one to each end of said envelope, a resilient arm secured to the opposite end -of each of said sheets, and means securing said arms one to each of said windings.

6. X-ray apparatus comprising a transformer including a rectangular core-type core having windings on a pair of opposite legs of said core, an X-ray tube comprising an elongate envelope and means mounting said tube on said windings including a pair of parallel, spaced apart sheets of silicone glass fabric laminate each having an aperture adjacent one end for receiving an end of tube envelope, means clamping said sheets one to each end of said envelope, a resilient arm secured to the opposite end of each of said sheets, a clamping ring detachably mounted on each -of said windings, and means securing said arms one to each of said rings.

7. X-ray apparatus comprising a tubular housing of X-ray permeable metal, a transformer mounted in said housing including a rectangular core-type of core having windings on a pair of opposite legs thereof, an Xray tube, means resiliently supporting said tube :between said windings with said tube positioned closely adjacent to but spaced from the wall of said housing, and shields of insulating material positioned between said housing and said tube at each of the opposite ends of the latter.

References Cited in the le of this patent UNITED STATES PATENTS 1,408,989 Coolidge Mar. 7, 1922 2,098,900 Hirsch Nov. 9, 1937 2,114,070 Bouwers Apr. l2, 1938 2,137,122 Humphreys Nov. 15, 1938 2,387,427 Atlee et al. Oct. 23, 1945 2,503,075 Smith Apr. 4, 1950 2,547,996 Boucher Apr. 10, 1951 2,593,526 Bell et al Apr. 22, 1952 2,637,818 Gund et al. May 5, 1953 FOREIGN PATENTS 548,722 Great Britain Oct. 21, 1942 

